The present invention relates to water skier alarm devices, and more particularly concerns an apparatus and system for automatically warning the operator of a skier tow-boat and the operators of nearby boats when a water skier being towed by said tow-boat either releases a skier tow-rope or falls into the water. The system of the present invention includes means for sensing when the rope-handle of a skier tow-rope is submerged in water or is otherwise released by a water skier, and means for indicating to the tow-boat operator and for warning operators of nearby boats when said skier releases said rope-handle or otherwise falls into the water.
During recent decades, water skiing has grown into a well known and extremely popular form of sport and entertainment. In this sport, a water skier standing on one or more of various forms of water skis and holding a handle end of a tow-rope is pulled across the surface of a body of water by a tow-boat to which the tow-rope is attached. Although water skiing is a relatively safe method of achieving the exhilaration that accompanies low altitude high-speed personal movement, it does entail certain elements of danger, such as boat-to-boat and boat-to-skier collisions. Unfortunately, as the popularity of the sport has increased, so has the density of water-skiers on the public waterways, which has understandably increased the risks of a skier's involvement in these dangers. Those familiar with the sport realize that the time of greatest risk is when a skier has either fallen and/or has released the tow-rope. Although it is relatively easy to spot the movement of a water skier tow-boat or a skier in-tow, it is extremely difficult to spot an individual who has fallen and/or has released the tow-rope and is "down" in the water, especially if the spotter is bouncing over the waves in a high speed boat.
To reduce the dangers associated with this period of greatest risk, many skier-down alarm devices have been proposed. Federal U.S. Coast Guard regulations and the laws of many states have dictated that the least complex of these devices become a mandatory item of use by participants in the sport. This device is the "skier-down" flag, which is to be flown by a boat whose water skier has fallen. The typical skier-down flag comprises an orange triangular pennant fixedly attached to a flag-end of a means for supporting said flag, such as a mast or flagstaff, and held up by a tow-boat operator or other person in the tow-boat during the entire time period in which a skier is down. The purpose of said skier-down flag is to alert nearby boats of the existence of a downed skier in their vicinity, and of the probability that the boat on which the skier-down flag is flying will be making maneuvers which are less predictable, as it turns to retrieve the downed skier. Many devices have been proposed to lessen the efforts required of a tow-boat operator, or said other individual in the boat, to locate, raise and hold-up said skier-down flag, such as those disclosed in the U.S. Pat. Nos. 3,786,778 (Palmer), 3,797,450 (Frisbee), 4,090,468 (D'Spain), and 4,122,796 (Pressler). In each of these is taught various means for securing to the boat, for raising, for holding in a position which is viewable by nearby boaters and lowering a skier-down flag.
Although this type of downed water skier warning device has addressed the work required by the tow-boat operator, or said other individual, it has failed to address other problems associated with this period of greatest risk, including the problem of alerting said operator or other individual to the fact that the skier has fallen and/or is down. The very nature of the operator task of maneuvering and operating a high speed tow-boat lowers his ability to ascertain the precise moment in which a skier falls. Even when an individual other than the operator is responsible for raising the skier-down flag, the lower levels of alertness that tend to accompany such a leisurely task often work to reduce the attentiveness of said individual. What makes this a critical point is that the skier-down flag is often the only warning which is visible to nearby boats pertaining to the hard-to-recognize downed skier. The longer it takes for a tow-boat operator to realize his skier is down, the farther said tow-boat and its raised downed-skier flag initially may be from said downed skier, increasing the time interval between the skier's fall and the moment in which other boaters in the vicinity recognize the potential danger.
Various efforts have been made to eliminate this particular aspect of the danger accompanying a downed skier via attempts to provide a device for automatically raising the skier-down flag after a skier has released the tow-rope, some of which are disclosed in U.S. Pat. Nos. 3,602,188 (Penaflor), 3,735,724 (Miller), 4,807,557 (Lodisio), and 3,798,631 (Langford). Each of these teach a warning device which is actuated via a type of tension-switch mechanism designed for sensing significant changes in the tension on the tow-rope between the skier's rope-handle and the tow-boat. Although each of the tension-switch actuated devices so disclosed attempt to address the problem of alerting the operator and/or other boaters after a skier has released the tow-rope, each of the devices of the prior art fails to address downed-skier problems which are resolved by the present invention. The operational basis for these tension-switch devices is the knowledge that in most situations said tension does significantly decrease when the skier drops the rope handle. However, these devices cannot alleviate problems that naturally occur when an indirect method of detecting when the water skier releases the rope-handle is utilized. Such devices fail to provide means for indicating between those planned events known to produce the downed skier alarm and those unforeseen events that can likewise precipitate said alarm, and thereby create occurrences of false alarms that tend to confuse the tow-boat operator and nearby boaters, if not actually teach outright disregard for said warning devices, vis-a-vis The Boy Who Cried Wolf. Various of these false alarm situations are described in conjunction with further description of examples of the prior art, below.
The disclosures of Penaflor, Lodisio and Miller each teach the use of a skier-down flag that is automatically raised when said tension has sufficiently decreased. The disclosures of Penaflor and Langford teach the actuation of a warning indicator for the tow-boat operator which is responsive to said tension-switch. Langford's disclosure does not teach the use of means for automatically raising a skier-down flag; however, it does disclose means for actuating an operator warning indicator such that said indicator cannot be turned-off until said skier-down flag is placed into means for holding said flag in an upright position, said means for holding further being mounted on the boat.
In Penaflor's disclosure a skier-down flag is mounted within a cylindrical enclosure positioned at the stern of a ski boat in which there is a spring for biasing the flagstaff upwardly out of the enclosure, for placing said skier-down flag in view of neighboring boats. The lower end of the skier-down flag is attached to a transverse line which is further attached to the skier tow-rope through an aperture in the transom of the tow-boat. As well as requiring an expensive installation, the device of this disclosure fails to take into account the often existing situation in which the tension on a skier's tow-rope is temporarily and significantly decreased, such as that which occurs when the skier comes off the crest of a wave, or when the skier has just undergone a rapid centrifugal acceleration about an arc of the tow-rope radius and is now decelerating while the tow-boat "catches-up" to the pace of the skier. Such slackening in the tow-rope tension thereby allows the spring-bias of the cylinder to move said skier-down flag up and down out of said housing, which creates a situation in which neighboring boaters have difficulty understanding the signal being delivered by the skier-down flag, and therefore may learn to ignore said flag.
The disclosure of Miller addresses some problems of Penaflor's disclosure by providing means for raising the skier-down flag which includes a pivotally mounted skier-down flag with a fluid dampened spring for biasing said flag in an up position. The skier-down flag is connected directly to a transverse line for holding the tow-rope, and is held in a down position against the upward biasing force of said spring by tension created via the skier being pulled on the tow-rope. Although the fluid dampening of the biasing spring accomplishes a lessening of the speed at which the flag is allowed to raise up and down during times of temporary slackening of the tension in the tow-rope, it fails to eliminate said temporary up and down raising. With the skier-down flag of this particular disclosure mounted in permanent view, the device of this disclosure provides yet another situation in which nearby boaters have difficulty understanding the message said skier-down flag is signaling. What makes the difference between the temporary slackening of the tow-rope and the actual release of the tow-rope by the skier even more difficult to decipher when using this device, is that a significant amount of tension is created on the rope-handle by the water itself after a skier has released said rope-handle and the tow-rope is being dragged through the water. Although the device of Miller is attractive due to its apparent simplicity, to overcome this problem of knowing the difference between actual skier-down situations and other false-alarm situations requires some training on the part of the operator.
The disclosure of Lodisio provides another attempt to overcome the problem of skier-down flags giving false alarms during temporary periods of slackened tension on the skier tow-rope. This disclosure teaches a device in which a skier-down flag is mounted within a cylinder against means for biasing said flag upward and out of said cylinder. The flag is further attached at its downward end to a pull rope which is attached to the skier tow-rope. This disclosure further teaches the provision of an aperture in the lower portion of the cylinder through which said pull rope passes. On the pull rope in the vicinity of this aperture are knots, or secured spheres, for dampening the movement of said pull rope through said aperture. Like Miller's disclosure, the dampening of the up and down movement of the skier-down flag may be useful for the boat operator, after he has learned to decipher the difference between a temporary slackening of the tow-rope and a tow-rope that has been released by the skier. However, one using this device cannot safely assume that the operators of neighboring boats understand the flag's signal until all tension has been taken off the rope, which usually occurs only when the boat has stopped to pick-up the downed skier, after a period in which said skier has had to fend for himself against nearby boat operators who remain unaware of a downed-skier situation.
Another problem with the downed water skier warning devices of Penaflor and Lodisio is in the enclosure of the flag within a hollow cylinder. Both disclosures teach placing the flag into said cylinder against a spring-like force for biasing the flag in an upward and outward direction. Said outward biasing renders an appearance of (if not an actual) danger to someone who might unsuspectingly place his head above and near the upward opening of said cylinder.
The disclosure of Langford teaches a more complex downed water skier warning device which uses an electric load cell attached to the tow-rope for detecting a released-rope situation and actuating an audible and visual indicator to the boat operator when such situation has occurred. Among the problems inherent in this particular device is that it depends upon the operator and/or another individual for raising the skier-down warning flag. As well, the problem of storing the skier-down flag in a place that allows for convenient access to the flag when the skier goes down, is not addressed by this disclosure. Both of these problems tend to decrease the use of the skier-down flag. Although said skier-down flag may be placed in its disclosed mounting structure after the operator of the tow-boat has turned the boat around, stopped to pick-up the downed skier and located the skier-down flag, this does not help to reduce the tremendous risks associated with the time interval during which other boaters are not alerted to the skier's fall.
Another problem inherent in all the tension-switch activated downed water skier warning devices of the prior art is that of not allowing a tow-boat operator to detect the dangerous situation that exists when his skier has fallen without releasing the tow-rope. This is a common occurrence among new skiers. In this circumstance, the skier flounders helplessly in the wake of the tow-boat in a posture which is also hard to detect by other boaters. Until the skier actually releases the skier rope handle, the tension-switch actuated warning devices of the prior art cannot accurately detect and/or signal a warning to the tow-boat diver or other boat operators that a problem exits. Another problem associated with the tension-switch actuated downed skier warning devices of the prior art is the inability of the tow-boat operator or other individual in the boat to override the warning device and raise the skier-down flag on his own at such times other than the occurrence of a significant decrease in tow-rope tension when he may deem it necessary.
While the downed water skier warning devices so disclosed in the prior art may be suitable for a particular purpose to which they address, it will be apparent to those skilled in the art that said devices would not be as suitable for the purposes of the present invention. With the exception of the skier-down flag itself, such prior art systems have also enjoyed little or no commercial acceptance for various reasons, including those described above.